3C7-72030-0 Tohatsu LABEL, INTERFERENCE

Illustration 1 g00838120
Schematic for the starting aid circuitTest Step 1. Inspect Electrical Connectors and Wiring
Illustration 2 g01152490
Pin locations on ECM connector (P1-10) Output 2 (starting aid)
Thoroughly inspect ECM vehicle harness connector J1/P1, and the firewall bulkhead connector.Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Perform a 45 N (10 lb) pull test on terminal 10 in the ECM connector.
Check the ECM connector (allen head screw) for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Check the harness and wiring for abrasion and for pinch points from the sensor to the ECM.Expected Result:All connectors, pins and sockets are completely coupled and/or inserted and the harness and wiring are free of corrosion, of abrasion or of pinch points.Results:
OK - Proceed to Test Step 2.
Not OK - Repair: Perform the following repair:Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled.Verify that the repair eliminates the problem.STOPTest Step 2. Use Caterpillar Electronic Technician (ET) to Check the Relay
Connect Cat ET to the cab data link connector.
Turn the ignition keyswitch to the ON position.
Access the special test"Starting Aid Output" on Cat ET. The "Starting Aid Output" test will enable output 2 when the test is active.
Begin the "Starting Aid Output" test and listen for the relay to click. You may need to be near the engine in order to hear the click.Expected Result:The relay activates when the special test is enabled.Results:
Yes - The ECM and vehicle components are operating correctly.STOP
No - Proceed to Test Step 3.Test Step 3. Use Cat ET to Check the ECM
Illustration 3 g01152497
Pin locations on Breakout T (10) Output 2 (starting aid) (65) - Battery
Verify that Cat ET is connected to the cab data link connector.
Turn the ignition keyswitch to the OFF/RESET position.
Disconnect the ECM vehicle harness connector J1/P1.
Connect a breakout T between ECM connectors J1 and P1.
Connect a voltage test lamp to terminal 10 (output 2) and terminal 65 (-Battery) of the breakout T.
Turn the ignition keyswitch to the ON position.
Access the special test "Starting Aid Output" on Cat ET.
Cycle the special test "Starting Aid Output" to "Active" and to "Not Active" and watch the voltage test lamp.
Stop the special test.Note: A multimeter can not be used in place of the voltage test lamp when the ECM outputs are being tested.Expected Result:The voltage test lamp turns on when the test is active. The voltage test lamp turns off when the test is not active.Results:
Yes - The voltage test lamp turns on when the test is active. The voltage test lamp turns off when the test is not active. The ECM is OK. The problem is in the vehicle wiring. Inspect the vehicle wiring and then repair the vehicle wiring. Otherwise, send the vehicle to the OEM dealer for repair. Verify that the original condition is resolved.STOP
No - The voltage test lamp does not turn on when the test is active. The voltage test lamp does not turn off when the test is not active. Temporarily connect a test ECM. Use the "Starting Aid Output Special Test" on Cat ET to check the ECM. If the problem is resolved with the test ECM, install the suspect ECM. If the problem returns with the suspect ECM, replace the ECM. Verify that the repair eliminates the problem.STOP